 #define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>

int main() {
    double term = 1.0, result = 1.0;
    int n;

    for (n = 2; n <= 100; n += 2) {
        term *= (double)((n * n) / ((n - 1.0) * (n + 1.0)));
    }

    printf("result=%f\n", 2 * term);

    return 0;
}